Abstract

Potentials of Spectrometry in Economic Rocks Mapping -A Brief Analysis for Three Economic Rocks of Three Different Geological Provinces of India

Ananth Rao D, Arindam Guha, Vinod Kumar K and Dhananjaya Rao EN

In this research article, we have demonstrated how spectrometric properties of diagnostic absorption features of rocks imprinted in their reflectance spectra can be used to delineate economic rocks (limestone, bauxite and gossans) from the adjacent country rocks. Spectral features or absorption features of rocks, discussed in this paper, are identified based on the comparative analysis of spectral feature of diagnostic constituent minerals of these rocks. It has also been observed that the each economic rock can be separated from their respective “background” country rock(s) based on the combination of certain spectrometric properties (wavelength of absorption feature and asymmetry) of their respective diagnostic absorption features imprinted in their reflectance spectra. The study also revealed that the separability of these economic rocks from their respective host rock will be affected if spectral profiles of mixed set up (where economic rocks are linearly mixed with the associated country rocks within the field of view of spectroradiometer) are collected instead of pure rocks. This observation justifies the fact that size of minimum distinguishable unit (i.e., pixel in case of spectral data presented as a image) of spectral measurement should be less than the size of the exposure/target, for effectively separating one pure target i.e., an economic rock from the associated country rocks.